Field of the Invention
The invention relates to an antenna, and particularly relates to a dual-band antenna.
Description of Related Art
Regarding a ceiling type communication device, a requirement on an antenna thereof is that a depression angle of a field pattern should be small enough in order to achieve sufficient signal coverage range. Generally, if the antenna is designed in a way of external antenna, a dipole antenna can be adopted to achieve a best coverage range. However, since a requirement of today's product design has a trend of small volume and simple shape, the antenna is required to be designed in a way of built-in antenna, and the dipole antenna generally has a too large size, which is not suitable for being disposed in internal of the device.